This section provides background information related to the present disclosure which is not necessarily prior art.
Camshaft phasers have been widely used in internal combustion engines to very valve timing to achieve purposes such as lower emissions, increase peak power at high revolution speeds and improve idle quality. Camshaft phasers are normally operated using pressurized hydraulic fluid which require engine operation. Accordingly, camshaft phaser systems are typically not capable of operation during engine off conditions. Engine start-up can be adversely affected due to a broad range of temperatures and can be improved by reducing the compression ratios at start-up. Accordingly, it is desirable to provide a camshaft phaser system that is capable of camshaft adjustment during engine off conditions in order to improve engine start-up with low-cost and minimum adverse impact on engine parasitic losses.